Device and method for vascular re-entry

ABSTRACT

In a method for re-entry from extraluminal space into the central lumen of a vessel, a guidewire is advanced into the extraluminal space of the vessel, and then a directional catheter is advanced over the guidewire through the extraluminal space. Thereafter, the guidewire is removed from the directional catheter, an ultrasound device is placed through the directional catheter, and the ultrasound device is advanced through the extraluminal space into the central lumen and then activated.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending U.S. application Ser.No. 13/551,424, filed Jul. 17, 2012, which is a continuation of U.S.application Ser. No. 12/456,143, filed on Jun. 12, 2009, issued on Jul.24, 2012 (now U.S. Pat. No. 8,226,566), all of which are herebyexpressly incorporated by reference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention pertains to media devices and methods, and moreparticularly, to a method and catheter system for accessing the centrallumen of a blood vessel from extraluminal space.

2. Description of the Related Art

There have been many procedures and systems for treating vascular orvenous obstructions that are occluded with atheroma, plaque or calcificmaterial, and are often referred to as vascular chronic total occlusion.In the past, such cardiovascular diseases were treated using a dramaticand painful surgical bypass procedure. However, a recent development ofcatheter-based interventions is less traumatic, and shows better successrates and long term patency.

The catheter-based interventional procedures require that a guidewire ispositioned through such an occlusion in a distal central lumen. In manyinstances, guidewire placement in the central distal lumen is difficultor almost impossible, mostly due to hard occlusive material or theinability to define a vessel path. Often, during such procedures, aguidewire deflects from the occlusion and penetrates into anextraluminal space (i.e., subintimal or outside the vessel). Frequently,a guidewire might perforate a vessel and end up outside of the vessel.While such perforations are very dangerous in certain circulations(e.g., in the brain and the heart), such perforations are less risky inperipheral arterial circulations and in most of the venous system due tomuscular tissue surrounding these areas.

Once in an extraluminal space, between layers of the vessel, it isdifficult or often impossible to re-enter a guidewire into the centrallumen even with the use of ancillary deflecting catheters or devices. Insuch cases, a catheter-based intervention cannot be performed andpatient well being relies on more complex and painful surgicalintervention.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an improved methodfor facilitating re-entry from extraluminal space into the central lumenof a vessel.

In order to accomplish the objects of the present invention, there isprovided a method for re-entry from extraluminal space into the centrallumen of a vessel. According to this method, a guidewire is advancedinto the extraluminal space of the vessel, and then a directionalcatheter is advanced over the guidewire through the extraluminal space.Thereafter, the guidewire is removed from the directional catheter, anultrasound device is placed through the directional catheter, and theultrasound device is advanced from the extraluminal space into thecentral lumen and then activated.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a human artery.

FIG. 2 is a cross-sectional view of a human vein.

FIG. 3 illustrates an artery or vein that has total occlusion.

FIGS. 4-11 illustrate a method according to the present invention forre-entry from extraluminal space into the central lumen using anultrasound device according to the present invention.

FIGS. 12-13 illustrate a follow-up stent placement after the stepsillustrated in FIGS. 4-11.

FIG. 14 is a perspective view of an ultrasound system that can be usedto carry out the method illustrated in FIGS. 4-13.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The following detailed description is of the best presently contemplatedmodes of carrying out the invention. This description is not to be takenin a limiting sense, but is made merely for the purpose of illustratinggeneral principles of embodiments of the invention. The scope of theinvention is best defined by the appended claims. In certain instances,detailed descriptions of well-known devices, compositions, components,mechanisms and methods are omitted so as to not obscure the descriptionof the present invention with unnecessary detail.

A blood vessel is an elastic tubular channel, such as an artery, a vein,or a capillary, through which blood circulates. Arteries transportoxygenated blood away from the heart with one exemption of the pulmonaryartery. FIG. 1 illustrates a normal healthy artery 100 having a centrallumen 101 and arterial wall with three layers: intima 102, intermedia103 and adventitia 104. All three layers consist of elastic tissue,smooth muscle and connecting tissue (collagen). The tissue of thearterial wall is often called a sub-intimal space. The area outside theadventitia 104, an external layer of the artery, is called a spaceoutside of the vessel. Both areas, sub-intimal space and outside thevessel space, are referred to collectively herein as “extraluminalspace”.

Veins transport de-oxygenated blood towards the heart with one exemptionof the pulmonary vein. FIG. 2 illustrates a normal healthy vein 200having a central lumen 201 and arterial wall with three layers as well:intima 202, intermedia 203 and adventitia 204. All three layers areidentical to the layers of the arterial wall and also consist of elastictissue, smooth muscle and connecting tissue (collagen). The walls of theveins are thinner and less elastic than the corresponding layers ofarteries, and transport blood at lower pressure than arteries. Veinsinclude valves that aid the return of blood to the heart by preventingblood from running in the reverse direction. The tissue of the vein wallis also called a sub-intimal space. The area outside the adventitia, anexternal layer of the vein, is also called a space outside of thevessel. Both areas, sub-intimal space and outside the vessel space, arereferred to collectively herein as “extraluminal space”.

A Total Occlusion (TO) is defined as an artery or vein that has beencompletely occluded. Acute Total Occlusions usually are associated witha sudden blockage and no blood flow to and from surrounding tissue, andare potentially life threatening. In contrast, Chronic Total Occlusions(CTO) are those that have formed for at least thirty days and are lesslife-threatening. In such cases, the areas around CTOs tend to developcollateral blood supply. FIG. 3 illustrates a total occlusion 301 thatusually consists of atheroma, thrombus, plaque, calcific material orcombinations of all of these materials. For illustrative purposes, anArterial Chronic Total Occlusion 301 will be shown in connection withthe method of FIGS. 3-11. However, all the methods described herein canalso apply to chronic total occlusions within veins. Such Chronic TotalOcclusion occupies the entire lumen, thus blocking blood flow. It hasbeen proven by several scientific publications that it is desirable toopen such Chronic Total Occlusions and restore blood flow throughaffected areas to improve blood supply and heart Left VentricularFunction. Examples of such publications include:

-   -   Immediate Results and One-Year Clinical Outcome After        Percutaneous Coronary Interventions in Chronic Total        Occlusions; Z. Olivari, P. Rubartelli, F. Piscione, F.        Ettori, A. Fontanelli, L. Salemme, C. Giachero, C. Di Mario, G.        Gabrielli, L. Spedicato, F. Bedogni on behalf of the TOAST-USE        Investigators; JACC, May 2003; Vol 41 No 10: 1672-1678    -   Outcome of PTCA and Stenting in Diabetic and Nondiabetic        Patients: A Report from the Total Occlusion Study of Canada        (TOSCA) Investigators; V. Dzavik, K. Yee, T. Anderson, E.        Cohen, J. Mancini, D. Catchier, G. Barbeau, J. Ducas, C.        Lazzam, J. Burton, P. Berger, C. Buller; JACC, March 2002: p.        28A    -   Procedural Outcomes and Long-Term Survival Among Patients        Undergoing Percutaneous Coronary Intervention of a Chronic Total        Occlusion in Native Coronary Arteries: A 20-Year Experience; J.        Suero, S. Marso, P. Jones, S. Laster, K. Huber, L. Giorgi, W.        Johnson, B. Rutherford; JACC, August 2001; Vol 38 No 2:409-414,

According to the present invention, methods and devices are provided tofacilitate re-entry of interventional devices, such as guidewires orcatheters, from an extraluminal space (or outside of the vessel) intothe central lumen of the vessel. If the chronic total occlusion islonger, such a re-entry can take place at any location along theocclusion. The re-entry can also be made into the existing occlusion ordistally beyond the occlusion.

Referring to FIGS. 4-11, in one embodiment, a guidewire 401 is passed inan extraluminal space and its distal end is positioned beyond the CTO301, or at a desirable location for re-entry into the distal centrallumen 101D, An access catheter or a deflecting catheter 501 is placedover this guidewire 401 either in a rapid exchange or over-the-wirefashion at the vicinity of the distal end of the guidewire 401. Theaccess catheter 501 is bent or curved at its distal end, and can bemanipulated and directed toward the distal central lumen 101D. Tofacilitate the correct positioning of the access catheter 501, a seriesof radiopaque markers 503 may be situated on the distal end of thecatheter 501, or the distal end of the catheter 501 may be made of aradiopaque polymer. The access catheter 501 may have a pre-shaped distalend 502 and should exhibit an excellent torque response characteristicand visibility under fluoroscopy to further facilitate directionalmovements. Once the access catheter 501 is positioned at the re-entryarea, the guidewire 401 is removed, and the access catheter 501 remainsin the subintimal space or outside the vessel.

An ultrasound or vibrational device 701 is then introduced through theaccess catheter 501 and positioned distally. When it is confirmed (underfluoroscopy) that the distal end of the access catheter 501 is directedtowards the distal central lumen 101D, the ultrasound device 701 isactivated and slowly advanced through the subintimal space to puncturethe vessel wall. After the ultrasound device 701 reaches the distalcentral lumen 101D, ultrasound energy activation stops and theultrasound device 701 is positioned further distally in the distalcentral lumen 101D. The distal end of the access catheter 501 isadvanced through the created re-entry pathway over the ultrasound device701 into central lumen 101. Subsequently, the ultrasound device 701 isremoved from the access catheter 501 and any guidewire 401 of choice (oranother catheter) may be positioned in the distal central lumen 101D viathe access catheter. Thereafter, the access catheter 501 is removed fromthe body, and with any conventional guidewire 401 located in the distalcentral lumen 101D, the patient is ready for a diagnostic orinterventional procedure.

In another embodiment, devices utilizing different sources of energy orforces may be used to re-enter the distal central lumen 101D from thesubintimal space, including but not limited to: vibrational devices,rotational device, cutting devices, radiofrequency devices, laserdevices, microwave devices and puncture devices.

In yet another embodiment of the present invention, in addition tofluoroscopic imaging, an intravascular ultrasound or other imagingmodalities may be employed, including Optical Coherence Tomography (OCT)or magnetic fields (Stereotaxis Inc.) to further facilitate orientationof the access catheter 501 towards the distal central lumen 101D andhelp in the re-entry procedure.

The apparatus of the present invention comprises an ultrasound systemthat includes an ultrasound device 701 and an access catheter 501. Sucha deflecting or directing catheter 501 has a catheter body having aproximal end, at least one lumen extending therethrough, and a distalend 502 that has a pre-formed bend or curve. The same deflectingfunction may be achieved with a catheter having an actuated distal end,as is well-known in the art. Such a bend should be suitable to deflectthe distal end of the ultrasound device 701. The deflecting catheter 501should have good torque response and good distal bend/shape retention.Both characteristics are important for positioning and manipulation ofthe deflecting catheter 501 while selecting directions toward the distalcentral lumen 101D. Both characteristics may be achieved using shapeablepolymers (with or without metal or polymer reinforcement systems) thatare well-known in the art. The shape and the length of shaped distal endof such a deflecting catheter 501 may vary in length between 1 mm-20 mmand in angle between 5-90°. The ultrasound or vibrational device 701 ofthe present invention may be an ultrasound or vibrational catheter,guidewire or a simple cannula, and may operate at frequencies between 10Hz and 20 MHZ in continuous mode, pulse mode or combination of both.Several examples of such devices are shown and described in U.S. Pat.Nos. 4,870,953; 4,920,954; 5,267,954; 5,304,115; 5,427,118; 5,989,208;6,007,514; 7,137,963; 7,220,293; 7,297,131; 7,335,180; 7,393,338;7,540,852 and in Pub. Nos. 20080108937 and 20080287804. The ultrasounddevice 701 can be provided with a self deflecting capability, as acatheter with an actuating distal end. Such a device may be used forre-entry from an extraluminal space without the use of a deflectingcatheter 501. If a guidewire ends up in extraluminal space, theultrasound device with a deflecting/actuated tip is introduced distallyin the subintimal space, and then deflected accordingly, activated andadvanced toward the distal central lumen 101D. Alternatively, apre-shaped ultrasound device may be used to re-enter from anextraluminal space without use of a redirecting catheter.

Referring now to FIG. 4, a guidewire 401 according to the presentinvention is advanced in a vessel until it faces the CTO 301. Sometimes,the guidewire 401 can be successfully advanced through the CTO 301 andpositioned in the distal central lumen 101D of the vessel 100. Once theguidewire 401 is in the central proximal lumen 101P, and beyond the CTO301, an adjunctive angioplasty such as balloon angioplasty and/orstenting can follow to complete an interventional procedure. However, asshown in FIG. 4, the guidewire 401 often deflects from the CTO 301 andpenetrates the vessel wall 100. The guidewire 401 in FIG. 4 is shown tohave penetrated the intima layer 102, and ending up between theintermedia 103 and adventitia 104 layers. The guidewire 401 can beadvanced within the vascular layers until it passes the CTO 301. It canalso be easily advanced more distally within the subintimal space.However, it is desirable that advancement of the guidewire 401 withinthe subintimal space be as short as possible, just beyond the proximalend of the CTO 301. Often, when CTOs 301 are long and there is evidenceof softer occlusion composition, the proximal advancement of theguidewire 401 should be limited as much as possible. If possible,re-entry within the CTO 301 should be considered as well to minimize thelength of the subintimal space which the guidewire 401 will occupy.Re-entry of the guidewire 401 from the subintimal space into the centraldistal lumen 101D may encounter serious difficulties, or the guidewire401 may be unable to re-enter into the central proximal lumen 101P, dueto the muscular vessel structure. In such cases, either a guidewire istoo soft to puncture the vessel wall, or the directing catheter providesinsufficient support, or both.

FIG. 5 shows a deflection catheter 501 having a shaped distal end 502that is introduced over the guidewire 401 in the subintimal spacebetween media 103 and adventitia 104. To provide better visibility, sucha deflecting catheter 501 may be provided with radiopaque markers 503 orcan be made of a radiopaque material for better visibility underfluoroscopy. The deflecting catheter 501 serves to direct the guidewire401 into the distal central lumen 101D. The guidewire 401 and thedeflecting catheter 501 may be advanced and manipulated in parallel orsequentially until the guidewire 401 is positioned in a direction thatfaces the central distal lumen 101D. Next, the guidewire 401 is removed.

FIG. 6 shows the deflecting catheter 501 still positioned within thesubintimal space between the media layer 103 and adventitia layer 104,after the guidewire 401 has been removed.

In the next step, an ultrasound device 701 is introduced. FIG. 7illustrates the defecting catheter 501 in the subintimal space, and withthe ultrasound device 701 (having a distal end 702) positioned throughthe deflecting catheter 501. Ultrasonic energy with its cavitationaland/or thermal effect(s) may be very helpful in ablating or penetrating,perforating or piercing the vessel wall 100, and then facilitatingre-entry into the central distal lumen 101D. Also, vibrational deviceswith longitudinal or transverse vibrational forces, rotational devicesor other heat generating devices such as radiofrequency or microwavedevices may also be used to facilitate re-entry into the central distallumen 101D. The ultrasound device 701 may be activated and then advancedthrough deflecting catheter 501 into the central distal lumen 101D.

Then, as shown in FIG. 8, the ultrasound device 701 is advanced into thedistal central lumen 101D and positioned beyond the CTO 301.

Next, as shown in FIG. 9, the deflecting catheter 501 is advanced overthe ultrasound device 701 from the subintimal space of the vessel wallinto the distal central lumen 101D to a location beyond the CTO 301.

FIG. 10 illustrates the deflecting catheter 501 positioned around theCTO 301 through the subintimal space and into the distal central lumen101D. The ultrasound catheter 701 is removed and replaced by theguidewire 401 which has been inserted through the deflecting catheter501 until its distal end is positioned in the distal central lumen 101D.

Next, the deflecting catheter 501 is removed. FIG. 11 illustrates theguidewire 401 positioned through the subintimal space of the vessel 100into the central distal lumen 101D, after the deflecting catheter 501has been removed. Such a guidewire position is required to continue aninterventional angioplasty, either a balloon and/or stent procedure. Anexample of a stent procedure is illustrated in FIGS. 12-13 below. Forexample, FIG. 12 illustrates the guidewire 401 extended from theproximal part of the vessel 100, through the subintimal space and intothe distal central lumen 101D of the vessel 100. A balloon catheter 800with a stent 801 carried thereon is delivered over the guidewire 401 andpositioned such that the distal part of the balloon 800 and the stent801 are located in the distal central lumen 101D, and the proximal partof the balloon 800 and the stent 801 are located in the proximal centrallumen 101P. As shown in FIG. 12, the balloon 800 and the stent 801extend across the entire length of the CTO 301. The stem 801 is thendeployed, and FIG. 13 shows the fully deployed stent 801 in the centrallumen 101. The upper part 803 of the stent 801 penetrates the vesselwall into the subintimal space, while the lower part 804 of the stent801 flattens and covers the CTO 301. With the stem 801 deployed in thecentral lumen 101, blood flow through the vessel 100 is restored.

In cases when the length of a CTO 310 is longer, such a re-entryprocedure may be performed at any suitable location, even within the CTO301, and not necessarily distally beyond the CTO 301.

In order to optimize the methods described above, an extensiveflouroscopical visualization from several X-ray machine angles may berequired. Such visualization is needed during positioning of thedeflecting catheter 501 to assure that its distal end 502 is directedtowards the central distal lumen 101D. Use of endovascular ultrasound orother visualization devices, either in arteries or in adjacent veins,may also help to facilitate directing of the deflecting catheter 501towards the distal central lumen 101D.

FIG. 14 illustrates an example of an ultrasound system according to thepresent invention that can be used for re-entry into the central lumen101 of a vessel 100. The ultrasound system includes an ultrasound device120 which has an elongate body having a proximal end 122 and a distalend 121. Even though the numeral designation 120 is used in FIG. 14, itcan be the same as the ultrasound device 700 described herein. Theultrasound device 120 can be an ultrasonic energy delivery member, or acatheter having at least one lumen extending longitudinally with anultrasound transmission member extending therethrough. The ultrasounddevice 120 having the proximal end 122 and Y-connector 123 isoperatively coupled by way of a device knob 124, and a slide collar 125to the ultrasound transducer 126. The ultrasound transducer 126 isconnected to a signal generator 127, which can be provided with a footactuated on-off switch 128. The signal generator 127 can be supported byan IV pole 129. When the on-off switch 13 is depressed, the signalgenerator 127 sends an electrical signal to the ultrasound transducer126, which converts the electrical signal to ultrasound energy. Suchultrasound energy subsequently passes through the catheter device 120and is delivered to the distal end 121. A conventional guidewire may beutilized in conjunction with the device 120 (not shown).

The ultrasound device 120 may be a catheter formed of a flexiblepolymeric material such as nylon (Pebax) manufactured by Atochimie, Courbe Voie, Hants Ve-Sine, France. The flexible catheter body is preferablyin the form of an elongate tube having one or more lumens extendinglongitudinally therethrough. The catheter body defines a main lumen (notshown). Extending longitudinally through the main lumen is an elongateultrasound transmission member (not shown) having a proximal end whichis removably connectable to the ultrasound transducer 126 via a sonicconnector (not shown) such that ultrasound energy will pass through theultrasound transmission member. As such, when the foot actuated on-offswitch 128 operatively connected to the ultrasound transducer 126 isdepressed; ultrasound energy will pass through the ultrasoundtransmission member to the distal end 121 of the ultrasound device 120.

In one embodiment, the ultrasound transmission member may be formed ofany material capable of effectively transmitting the ultrasonic energyfrom the ultrasound transducer 126 to the distal end 121 of theultrasound device 120, and is preferably made from metal or metalalloys. It is possible to form all or a portion of the ultrasoundtransmission member with one or more materials which exhibitsuper-elasticity. Such materials should preferably exhibitsuper-elasticity consistently within the range of temperatures normallyencountered by the ultrasound transmission member during operation ofthe ultrasound device 120. Specifically, all or part of the ultrasoundtransmission member may be formed of one or more metal alloys known as“shape memory alloys”.

Examples of super-elastic metal alloys which are usable to form theultrasound transmission member of the present invention are described indetail in U.S. Pat. No. 4,665,906 (Jervis); U.S. Pat. No. 4,565,589(Harrison); U.S. Pat. No. 4,505,767 (Quin); and U.S. Pat. No. 4,337,090(Harrison). The disclosures of U.S. Pat. Nos. 4,665,906; 4,565,589;4,505,767; and 4,337,090 are expressly incorporated herein by referenceinsofar as they describe the compositions, properties, chemistries, andbehavior of specific metal alloys which are super-elastic within thetemperature range at which the ultrasound transmission member of thepresent invention operates, any and all of which super-elastic metalalloys may he usable to form the super-elastic ultrasound transmissionmember.

The frontal portion of the Y-connector 123 is connected to the proximalend 122 of the ultrasound device 120 using techniques that arewell-known in the art. An injection pump 130 or IV bag (not shown) orsyringe (not shown) can he connected, by way of an infusion tube 131, toan infusion port or sidearm 132 of the Y-connector 123. The injectionpump can he used to infuse coolant fluid into and/or through the device120. Such flow of coolant fluid may be utilized to prevent overheatingof the ultrasound transmission member and serves to bathe the outersurface of the, ultrasound transmission member, thereby providing for anequilibration of temperature between the coolant fluid and theultrasound transmission member. The temperature and/or flow rate ofcoolant fluid may be adjusted to provide adequate cooling and/or othertemperature control of the ultrasound transmission member. Theirrigation fluid can include a pharmacological agent and/ormicrobubbles.

In addition to the foregoing, the injection pump 130 or syringe may beutilized to infuse a radiographic contrast medium into the catheter 120for purposes of imaging. Examples of iodinated radiographic contrastmedia which may be selectively infused into the catheter 120 via theinjection pump 130 are commercially available as Angiovist 370 fromBerlex Labs, Wayne, N.J. and Hexabrix from Malinkrodt, St. Louis, Mo.

The distal end 121 of the ultrasound device 120 may have a separatedistal tip positioned on the ultrasound transmission member, asillustrated in U.S. Pat. No. 7,137,963 (FIG. 2). Alternatively, thedistal end 121 of the ultrasound device 120 may be the end of theultrasound transmission member, as illustrated in U.S. Pat. No.5,304,115 (FIG. 14). Also, the ultrasound device 120 may itself be aguidewire that is energized by ultrasound energy, as illustrated in U.S.Pat. No. 5,427,118. The proximal end of the ultrasound transmissionmember is attached to a sonic connector (not shown), which is configuredto effect operative and removable attachment of the proximal end of theultrasound transmission member to the horn of the ultrasound transducer126. The sonic connector is preferably configured and constructed topermit passage of ultrasound energy through the ultrasound transmissionmember with minimal lateral side-to-side movement of the ultrasoundtransmission member while, at the same time, permitting unrestrictedlongitudinal forward/backward vibration or movement of the ultrasoundtransmission member. Examples of ultrasound systems that includeultrasound transmission members (and their distal tips), ultrasoundtransducers, sonic connectors and their connections that can be usedwith the ultrasound device 120 are illustrated in U.S. Pat. Nos.6,427,118; 6,702,748; 6,855,123; 6,942,620; 6,942,677; 7,137,963;7,220,293; 7,297,131; 7,335,180; 7,393,338; 7,540,852 and in Pub. Nos.20080108937 and 20080287804 whose disclosures are incorporated by thisreference as though set forth fully herein.

While the description above refers to particular embodiments of thepresent invention, it will be understood that many modifications may bemade without departing from the spirit thereof. The accompanying claimsare intended to cover such modifications as would fall within the truescope and spirit of the present invention.

What is claimed is:
 1. A kit comprising: an energy catheter adapted tosupply energy to the outside of the wall of the central lumen locatedwithin a body when a distal end of the catheter is locatedextraluminally to the vessel; and an access catheter adapted to enterthe extraluminal space and guide an energy catheter into theextraluminal space.
 2. The kit of claim 1 wherein the energy catheter isbased on any one or any combination of the following energies:ultrasound, vibrational, rotational, radiofrequency, microwave or laser.3. The kit of claim 2 wherein the energy catheter comprises a proximalend outside of the body and an energy source is adapted to deliverenergy to the proximal end of the energy catheter.
 4. The kit of claim 3wherein the energy is ultrasound.
 5. The kit of claim 4 wherein theenergy catheter comprises an ultrasound transmission member that isadapted to receive energy from the energy source at the proximal end ofthe energy catheter and adapted to transmit energy to the distal end ofthe energy catheter.
 6. The kit of claim 5 wherein the ultrasoundtransmission member comprises a super-elastic material.
 7. The kit ofclaim 6 wherein the energy source includes a control device comprisingcircuitry to select between operation modes including continuous, pulse,or a combination of both.
 8. The kit of claim 7 wherein the controldevice further comprises circuitry to vary the ultrasound frequency from10 Hz to 20 MHz.
 9. The kit of claim 8 wherein the proximal end of theenergy catheter fluidly communicates with the distal end of the energycatheter and the energy catheter comprises a proximal port that connectscooling fluid to the proximal end of the energy catheter.
 10. The kit ofclaim 9 where in the distal end of the ultrasound transmission membercomprises a tip.
 11. The kit of claim 10 wherein the access cathetercomprises a curved or bent distal end.
 12. The kit of claim 11 whereinthe access catheter comprises a deflectable or steerable tip.